A Shell and Tube Heat Exchanger consists of a series of tubes, where one fluid flows through the tubes and the other fluid flows around the outside of the tubes within a larger shell. The fluids exchange heat through the walls of the tubes. The design maximizes the heat transfer area within a compact footprint, which is why it is a popular choice for heat transfer applications in indu... https://www.finfancooler.com/Heat-Exchanger/Shell-and-Tube-Heat-Exchanger/